1. Field of the Invention
The present invention relates to a magnetic position sensor, and more particularly to a magnetic absolute position sensor.
2. Description of the Prior Art
As shown in FIG. 1, a conventional optical position sensor 90 comprises a grating 91, a light emitter 92 and a light receiver 93. The grating 91 includes a light transmitting portion and a light tight portion. The light emitter 92 emits light toward the grating 91, the light partially passes through the light transmitting portion and reaches the light receiver 93 and is partially stopped by the light tight portion and unable to reach the light receiver 93. The light transmitting portion and light tight portion of the grating 91 are used as identification index to determine the absolute position of the optical position sensor 90.
However, the light emitter 92 and light receiver 93 of the optical position sensor 90 are located at opposite sides of the grating 91, if there are disturbing factors in the working environment, such as fog, smoke, dust and moisture and etc, the light receiver 93 will be unable to receive the correct signals.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.